Rockwell Automation 2706 DL20 SERIES G USER MANUAL - Manual (Page 86)

Chapter 7
The Parallel Port
7–14
If messages don’t contain variable data, the number of outputs can be
reduced. Since no variable data is transferred, both strobe lines are always
zero, or always one. In addition, some data lines (D0 - D9) could be
eliminated depending on the highest message number used.
Figure 7.3 illustrates this method.
Figure 7.3
11 Ouput Configuration
+
-
D9 D8 D6 D5 D4 D3 D2 D1 D0 MS0 MS1 GND
11A 11B 12 13 14 15 16 17 18 19 21 20 23
Terminal
Number
Terminal Block
Designation
Power Supply
5-30 VDC
(Observe DC
Polarity)
PC Outputs (11)
D7
You can further reduce the output requirements by tying the strobe lines high
as shown in Figure 7.4
Figure 7.4
10 Output Configuration
Tie Together
For HIGH
TRUE Logic
Only
+
-
D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 MS0 MS1 GND
11A 11B 12 13 14 15 16 17 18 19 21 20 23
Terminal
Number
Terminal Block
Designation
Power Supply
5-30 VDC
(Observe DC
Polarity)
PC Outputs (10)
Reducing Host
Output Requirements